Since this is professional industrial software, it is best to stick to official channels to ensure file integrity and security: Siemens Industry Online Support (SIOS):
This is the only official location.
Warning: Be cautious of third-party websites offering "free" or "cracked" downloads of engineering software. Downloading executable files from unverified sources can introduce malware into your network, which poses a massive security risk—especially in critical infrastructure environments like power substations. Digsi 4.90 Download UPD
If you are using Windows 10, it is highly recommended to use a more recent version than 4.90 to ensure stability: Since this is professional industrial software, it is
DIGSI 4 V4.94 SP1: Requires manual installation of .NET Framework V3.5 on Windows 10 for IEC 61850 devices to function properly. If you are using Windows 10 , it